<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Hi all,<div> I am using GMX4.5.1 to do COM pulling .</div><div> ; COM PULLING </div><div>; Pull type: no, umbrella, constraint or constant_force</div><div>pull = umbrella</div><div>; Pull geometry: distance, direction, cylinder or position</div><div>pull_geometry = direction</div><div>; Select components for the pull vector. default: Y Y Y</div><div>pull_dim = N N Y</div><div>; Cylinder radius for dynamic reaction force groups (nm)</div><div>pull_r1 = 1</div><div>; Switch from r1 to r0 in case of dynamic reaction force</div><div>pull_r0
= 1</div><div>pull_constr_tol = 1e-06</div><div>pull_start = yes</div><div>pull_nstxout = 10</div><div>pull_nstfout = 1</div><div>; Number of pull groups </div><div>pull_ngroups = 1</div><div>; Group name, weight (default all 1), vector, init, rate (nm/ps), kJ/(mol*nm^2)</div><div>pull_group0 = refer</div><div>pull_weights0 = </div><div>pull_pbcatom0 = 0</div><div>pull_group1 = K</div><div>pull_weights1 = </div><div>pull_pbcatom1 =
0</div><div>pull_vec1 = 0.0 0.0 1.0</div><div>pull_init1 = 0.0</div><div>pull_rate1 = 0.001</div><div>pull_k1 = 1000</div><div>pull_kB1 = </div><div><br></div><div>I don't know why it did not pull in Z direction? And what does pull_start = yes mean?</div><div>Thanks !</div><div>Zhongjin He</div></td></tr></table><br>